No, they aren't the same. Jump Comics is a broader category that may include various types of comics, while Shonen Jump specifically focuses on comics targeted at young male readers.
Not at all. Shonen manga is a broad category, and while Shonen Jump is a well-known and significant publisher, there are numerous other publishers and online platforms that feature shonen manga. It's a diverse landscape with various options for fans to explore.
Most of the time, the One Piece manga has a weekly release schedule. However, sometimes the author might need a break for health or creative reasons, or there could be production issues that cause a delay.